Marco Haller outsprinted some big-name rivals to claim his first professional victory on stage four of the Tour of Beijing.

The 21-year-old Katusha rider latched onto Alessandro Petacchi's wheel on the flat finish outside the Changping Stadium and then kicked on in the dying stages to edge out the Lampre man and his Italian compatriot Elia Viviani.

Tony Martin, meanwhile, was also part of that sizeable front group which ensured he maintained his 40-second advantage over Francesco Gavazzi with one stage remaining.

The penultimate day of action had seen the riders travel 165.5km from Yanqing and after numerous early attacks, five men managed to escape the clutches of the bunch and saw their advantage grow to six-and-a-half minutes during the first 65km.

Jeremy Roy was part of that quintet but shed his accomplices on the descent of the day's first climb and pressed on alone as the other escapees remained in tact.

The four riders behind would be caught in the last 15km, and Roy would only survive another 9km as several lead-out trains asserted their authority on the bunch.

Saxo Bank-Tinkoff Bank, Lotto Belisol and Orica-GreenEdge all took turns on the front as the race neared its conclusion, but as they passed onto the closing straight the action shifted towards the barriers and it was there that Haller found himself perfectly positioned behind Petacchi.

The Austrian bided his time brilliantly before jumping out of his rival's slipstream and taking his maiden victory with a bike length to spare.